Abstract # 105:

Scheduled for Saturday, September 17, 2011 07:00 PM-09:00 PM: Session 14 (Salon G (Sixth Floor)) Poster Presentation


E. Finestone1, K. Bonnie2, V. Vreeman1, S. R. Ross1 and E. V. Lonsdorf1
1Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, 2001 N Clark St, Chicago, IL 60614, USA, 2Beloit College
     The foraging activity of chimpanzees is a complex behavior because individuals must not only balance personal preferences, nutrient requirements and food availability [Sousa and Matsuzawa, 2006], but must also cope with social factors such as hierarchy and dominance effects. To examine how these factors may influence chimpanzee food selection we presented six zoo-housed chimpanzees with pair-wise combinations of hoisin sauce, ketchup, mustard and peanut butter in both social and individual conditions. First, we tested subjects in a social setting using an artificial termite mound baited with all possible binary combinations of the substances. We observed food choices using group scan-sampling with a 30-second inter-sample interval for one hour following baiting. In a subsequent experiment, the same subjects were presented with the same choices while temporarily separated from their social group. We presented substances on a portable tray until we completed 30 trials for each substance combination. A two-factor ANOVA indicated that subjects expressed significant preferences in both the individual and social setting (p=0.000, F=27.251). We also found a significant interaction effect between substance and condition (p=.002, F=5.232) such that a low-preference substance, mustard, was avoided more frequently in the individual condition than when the subject was in a group setting. These results suggest that while preferences remained consistent between social and individual environments, chimpanzees may alter their food selection criteria in a social context.